Steam-engine.



J. STU MPF.

STEAM ENGINE.

APPLIOATION FILED AUG. 25, 1910.

Patented Nov. 5, 1912 2 SHEETS-SHBET 1.

J. STUMPF.

STEAM ENGINE.

APPLIOATION FILED AUG. 25, 1910.

- Patented NOV. 5, 1912.

2 SHEETS-SHEET 2.

UNITED sTATEs .PATENT oEEIoE.

JoHANNsrUMrF, or BERLIN, GERMANY.

STEAM-ENGINE.

lf'o all whom' 'it may concern:

Be it known that I, JOHANN STUMPF, a

#subject of the King of Prussia, residing at in which the steam is admitted to the end of the cylinder past an inlet valve and exhausts through ports controlled by the piston at and near the end of its stroke.

The object of the present invention is to provide means for withdrawing compressed steam from such engines and into a separate receiver. lt is to be noted that the steam is not interferedwith during the working stroke, which proceeds in the ordinary way and according to this invention the steam -rapped in the cylinder after the exhaust ports yare closed by the piston is compressed tot wart oi the return stroke and then withun yn and supplied to the receiver or'coni pressed steam. For this purpose a connection is preferably provided leading through the piston, which is closed and hollow and communicates withthe receiver, and in this connection and carried by the piston there is a valve, the motion of which is interdependent upon the piston in such a way that the said valve closes said connection during the working stroke of the piston and the first part of the return or compression stroke and is then operatedl to establish communication, through said connection, between. the interior of the cylinder and the receiver for compressed steam.

By working stroke and compression stroke is of course meant the working and compression strokes with respect to any given side oi'- the piston; thus during any single travel of the engine the working stroke on one side is being carried out simultaneously with the compression stroke on the other side ot' the piston.

The improved engine will be more readily understood from the following description of one form illustrated by way of example in the accompanying drawings, in Which:-

Figure ll is a sectional elevationthrough the rear half of a horizontal uni-directional flow steam engine according to this invention. Fig. 2 is a similar sect-ion through the Specification of Letters Patent.

Application led August 25,

Patented Nov. 5, 1912.

1910. 'serial No. 578,831.

cross head and crank case of the engine. Fig. 3 is a hypothetical pressure-volume diagram, illustrating the operation of the engine.

According to the form of the invention shown, the working steam enters the hollow cover b, by the inlet pipes a, from which it passes, past the valves c, into the cylinder d. When that edge of the piston z', which acts as the controlling means for the exhaust ports, uncovers the exhaust ports o, the expandedsteam exhausts through the ports 0, in the cylinder walls and passes oi by the exhaust pipe 0, to the atmosphere or a condenser.v or some other auxiliary apparatus for further use. one end of the cylinder steam space and exhausty at the end thereofremote from that at which it enters and this constitutes the 'essential of a uni-directional'iiow steam engine. In the exhaust passage o', there is arranged a throttling member shown as a butterfly valve f, which is adapted to be con'- trolled by any suitable means dependent upon the pressure in the compressed steam receiver 2. In the drawing a controlling motor g, is indicated and this motor is connected by a pipe g, tothe compressed steam receiver 2, wherebythis motor'will respond to fluctuations in the pressure of steam in the receiver 2. The operating rod g2, of the motor g,`isconnected to the arm f of the buttertly valve f, sothat when the rod g2, sinks, the `valve f, is caused to obstruct the exhaust pipe 0, to a greater extent and thereby throttle the exhaust. This has the effect of leaving more steam to be trapped in the cylinder when the exhaustports 0, are covered by the controlling edge ofthe hollow pist-on z'.

The'piston i is in the form of a closed hollow body, the interior of which is connected by a hollow tail rod i', to the compressed steam receiver 712, and the ends ofthe piston lhave circular openings or bores whereby a connection is formed through the hollow piston z', and hollow tail rod i', between the interioryoiE the cylinderA at each side of the piston and-the compressed steam receiver 2. In this connection I arrangeA a valve h, the motion of which is interdependent upon that of the-piston z', in such a man-`v ner that the said valve breaks the communif cation between the interior of the cylinder on that side of the piston which is carrying out its workingstroke and the compressed The steam thus enters at los tween the compression side of the piston and the receiver i?, and then the valve is closed shortly before the piston reaches the end of its stroke. rThis cycle of operations will be readily followed from the-hypothetical diagram in Fig. 3.

In the form of this invention illustrated the compressed steam is Withdrawn through `the valve 7L, arranged in'the hollow piston t, and passes through the hollow piston z', rearwardly through the hollow tail rod t. The

valve L, is operated by a. rod 7L, which is l connected to a slide in the crosshead of the engine which slide is operated by an arm 7c, on the crosshead end of the connecting rod so as to open and close the valve k, at the desired times.

desired the valve e, may be arranged to open betere the main exhaust ports 0, are covered by the piston Any suitable means may be provided 'for insuring that the compressed steam passing to the receiver is ot a desired predetermined pressure. The

s means shown is, however,the preferable form and comprises what mightbe called a compound or. duplex valve control. rl`his compound valve control consists of the mechanically ope-rated valve and spring controlled valves m and mf, located in series with the valve h, and behind said valve with respect to the interior or". the cylinder-that is to say the spring controlled valves m and m are located between the valve h and the compressed steam receiver The residual or trapped steam in the cylinder., in this case, will be com nessed when the steam passage in the piston valve fi is closed by the springcontrolled valves m and m, as is illustrated in Fig. l, and said steam passage in the piston valve L will only be opened by one. or other of the valves m and 'mf when the rcsidual steam has been compressed up to the desired pressure, represented in the hypothetical diagram in F ig. S, by the horizontal line When the desired pressure is reached steam continues to pass olif thangh the valve L and the valve m or m as l s case may be, until the valve fr, closed this conveniently takes place after about fi-Gills of 'the compression stroke on each side of` the piston so as as to give suilicient cushioning.

In the form of the invention illustrated the engine is double acting and 'the piston valve 7a. is in two co-axial ported end parts and both the valves m and mi are (2o-axial with the valves z. and ci'mtrol the ports therein being acted upon by a common spring interposed betwecn them.

l claim:

l. ln a steam engine, a cylinder having a. steam inlet port ut its end and separate exhaust ports at an intermediate point in its lel'igth, a working piston in said cylinder and adapted to uncover said exhaust ports at the end of its Working stroke and on its return to close said exhaust ports and compress the steam trapped in the cylinder, a receiver for compressed steam, a connection from said receiver to the interior ot' said piston, means interdependent upon the motions oit the piston and operable to' close said` connection during the working stroke and the first part ot the compression stroke of the piston and to open said connection for a second part olf the compression stroke, substantially as described.

2. .ln a vsteam engine, a. cylinder having a steam inlet at. its end and separate exhaust ports at an intermediate point in its length, a closed hollow working piston .in said cylinder and adapted to uncover said exhaust ports at 'the end ot' its working stroke and on its return to close said exhaust ports and compress the steam trapped in the cylinder, a compressed steam receiver, a connection leading through said hollow piston vfrom the cylinder interior to said compressed steam receiver, a valve in said connection, said valve being closed to break said connection during the Working-stroke of the piston and the first part ot the compression stroke and being .opened to establish connnunication between the cylinder and the compressed steam receiver a'fter the piston. has compressed the steam trapped in the cylinder.

in a steam engine, a cylinder 'having a steam inlet at its end and separate exhaust ports at an intermediate point in its length, a closed hollow Working piston in said cylinder and adapted to uncover said exhaust ports at the end ot' the working stroke and on its ret-urn to close said exhaustI ports and compress the steam trapped in the cylinder, a compressed steam receiver, a connection leading through said hollow piston from the cylinder interior to said compressed steam receiver, mechanically operated valve in the piston and controllingsaid connection, and means for operating said valve interdependent upon the motions of the piston to hold said valve closed during the Working stroke of the piston and the lirst part of the compression stroke and being opened to establish communication between the cylinder and the compressed steam receiver after the piston has compressed the steam trapped in the cylinder.

lltl

l. ln eomlainetion, e seen cylinder lieving; inletpo's and seperate exhaust ports., e hollow piston in seid eylnideiq adapted to uncove' said exhaust pores ef "die end of its working stroke, and Ineens for withdrawing eolnpeseed 'eednel seem coinpieing e velve in seid piston for operating seid valve freni e. moving? peri; the engine lo place said hollow pieton in oomnunicaion with elle compression Spee-e ef the Gylinde?, means for Withd'ewing seam from seid hollow pison, e thi'ottling member for the' exhaust steam and means dependent upon the pressure of the residual steam einer leaving said hollow piston for con trolling seid thi'olbling member.

lin a steam engine7 a. cylinder having e steam inletet its end end seperate exhaust ports el; en intei'inediele point in its length, e closed hollow Working "pieton in said eylindcr and adapted to uneever seid exhaust )oi-ts et lie end of its Walking stroke and on te reinen to elose said exhaust poets and chanically operated valve operated wierde-v pendently upon the motions of' the pieton lte be closed dering; the working stroke and the latter part of the compression srole end n spring controlled valve in series with said mechanically operated valve and loce'ied behind Seid valve in respect to the interior of the cylinder.

In testimony whereof l have signed my naine to thie Specification in the presence of two subscribing witnesses.

JOHANN STUMPF.

l/Vitnesses JonA Nnns HEYNEMAN n, FRAN z Mii LLER. 

